Rifling twist rate question

Discussion in 'Ammo & Reloading' started by phideaux, Mar 5, 2013.

  1. phideaux

    phideaux Well-Known Member Lifetime Supporter

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    I didnt know where else to ask this, hope its ok here. If not, feel free to relocate.:)

    I reload a .223 round.
    It uses a 55grn bullet.

    I fire that round thru a 24" barrel with a 1:12 twist rate,
    I fire the EXACT same loaded round thru a 20" barrel with a 1:9 twist rate.

    QUESTION....

    What would results be as far as accuracy, at 100 yds ?,
    Keep in mind, EVERYTHING is exactly the same, except the barrel length and rate of twist.

    I have my own thoughts/opinion, but would like to hear from you guys.

    Anybody here that can shed any light on this?
    What do you think would change, if anything ?

    Jim
     
  2. Win94ae

    Win94ae New Member

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    I'm assuming you are implying that you cannot stabilize one or the other?

    I've shot bullets that my rifle would not stabilize, (slight keyholing,) but the precision was wonderful. They simply lost oomph at distance.
    [​IMG]
    That is my 30-06 shooting 3 shots using my the Hornady 220gr RN load at 400 yards. The load is going about 2350fps, so they don't quite stabilize.

    This is the same day shooting 3 shots with the same rifle, using Hornady 180gr SPBT at 400 yards. They're going about 2700fps so they stabilize with no problem.
    A short video of that group.
    [ame]http://www.youtube.com/watch?v=QV9I-Cu0z3g[/ame]

    I've had the same experience with precision with all of the bullets I couldn't stabilize.

    If you're not talking about stabilization, you'll have to be more specific.
     
    Last edited: Mar 8, 2013

  3. phideaux

    phideaux Well-Known Member Lifetime Supporter

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    Im not really talking about stabilizing a particular bullet.
    I understand that a 90 grn.223 bullet out of a 1:14 twist barrel simply will not stabilize.

    What Im seeking, I think:confused:, is .....
    with all things being exactly the same, except the barrel length and rate of twist, how would accuracy be affected at 100 yds.

    Using a 24 " barrel with 1:12 twist
    Using a 20 " barrel with 1:9 twist

    this is just something Im thinking about, as for deciding to make a purchase of a .223 coyote rifle.
    All .223 rifles I own now, are 1: 9 twist, am looking at a rifle with 1:12 twist.

    I may have to just go ahead and purchase it, and try my reloads until I MAY find one that works equally well in both,if thats even possible.

    thanks for replying win94.

    Jim
     
    Last edited: Mar 8, 2013
  4. SHOOTER13

    SHOOTER13 RETIRED MODERATOR Lifetime Supporter

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    General rule of thumb: The heavier the bullet, the faster the twist rate to stabilize it.

    For 5.56/.223 bullets weighing between 35 and 50 grains... use a 1:12 or even 1:14 twist.

    For 5.56/.223 bullets weighing between 50 to 70 grains... the 1:9 or 1:10 is the best.

    For 5.56/.223 bullets weighing between 70 to 90 grains... use a 1:7 or 1:8 twist.
     
  5. phideaux

    phideaux Well-Known Member Lifetime Supporter

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    Will I be able to take either of these two barrels, use exactly the same bullet weight ,55 gr, and sucessfully dial in sub MOA shots ? At exactly same distance?

    Jim
     
    Last edited: Mar 8, 2013
  6. SHOOTER13

    SHOOTER13 RETIRED MODERATOR Lifetime Supporter

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    Yes...as long as you do your job, that 55 grain bullet out of either barrel length / twist rate will do it's job.
     
  7. phideaux

    phideaux Well-Known Member Lifetime Supporter

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    Thanks for the reply.

    I was thinking it would.

    But I think you would see a difference in them at 5-6 hundred yds.


    Jim
     
  8. SHOOTER13

    SHOOTER13 RETIRED MODERATOR Lifetime Supporter

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    ^^ Very true....but you put the criteria at 100 yards. ^^
     
  9. phideaux

    phideaux Well-Known Member Lifetime Supporter

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    You are exactly right, I did.

    I should have said , I would like to see what the diiference would be at longer distances.

    we agree on the initial question of what would happen at 100 yds, with 55 gr bullet from the 2 barrels.:cool:

    I think you would see different outcome ,if you change that bullet to a 70gr bullet.
    agree?


    Jim
     
  10. giturgun

    giturgun New Member

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    I have a custom Pac-nor 1-9 twist , tight neck 28 inch straight taper barrel in 220250 on a 112 Savage, It shoots 50 to 69 gn bullets just fine.

    Have a Rem 700 22-250 1-12 twist. It shoots 50 / 60 gn bullets just fine ..

    Accuracy in both is good , though the 1-9 likes the heavier better. I have used 77 gn in it and it shoots them good as well.

    The Rem likes 55 gn slightly better than anything else
     
  11. phideaux

    phideaux Well-Known Member Lifetime Supporter

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    I think you are backing up my thinking.

    I think you would have accuracy problems at almost any distance, if you shoot a 77gr or 80 gr bullet out of a 1:12 barrel.

    I also think you would have problems,if you shoot a 36 gr bullet out of a 1:7 twist barrel. Too much rpms may disentegrate the bullet.

    Just my deduction from reading and chating,as I have not tested these situations.


    Jim
     
    Last edited: Mar 9, 2013
  12. barnetmil

    barnetmil New Member

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    This for me is one of the most interesting and informative posts that I have read on twist, stability, and long range accuracy. In full 30 cal cartridges I have also preferred the 1 in 10" twist as was the original military 30-06 barrels and could not understand how people were shooting longer bullets in the 1 in 12 308s and getting decent accuracy. Apparently if the bullet is concentric and also the loaded round even with a little wobble the uncompletely stabilized bullet can still shoot a pretty good group.
    By the way, what rate twist were you shooting with your 30-06?
     
  13. giturgun

    giturgun New Member

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    Have about settled on the 60 gn Hornady hp in the 1/9 twist barrel.


    I had a 1-9 .223 barrel and cut the threads off 1/4 inch , rechambered to .222. I don't like the results so it will be a .223 again. If that don't suit me it will either be a 22-243 Middlestead or a 22-06. Always have wanted either or both of these
     
  14. giturgun

    giturgun New Member

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    And I have shot 40 gn balistic tips in the 1-9 . not very accurate, but they don't blow up . Could be due to the tight neck and short land / lead , I run the very minimum neck clearance possible. It isclose enough to Not have to resize brass to reload it. just re-prime and load. no neck size . But I do size with a Redding bushing die. My brass for this one is turned to .249/.2495 The neck is .250.
     
  15. Win94ae

    Win94ae New Member

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    1 in 10.

    Thank you!
     
  16. giturgun

    giturgun New Member

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    Have never checke mine , whatever Ruger had in the mk 2 ultralite ss . Have a take off Savage barrel that I have never even mounted on the receiver , got it in a trade when I helped my nephew put an aftermarket barrel on his 110.
     
  17. phideaux

    phideaux Well-Known Member Lifetime Supporter

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    Well,
    I made a decision,
    I will be picking up a Savage 11 XP Trophy Hunter this week.

    It has 1:9 twist rate , as all my .223 rifles.
    I will use it to work up reloads, and do a little Coyote huntin.
    It dont have a 24" barrel or a 20" barrel.
    I has a 22" barrel.
    Comes with accutrigger and Nikon Prostaff 3X9X40 .

    I just wantwed something to test loads close to all my rifles.
    1:12 twist in H&R rifles was just too far apart.


    Jim
     
  18. SHOOTER13

    SHOOTER13 RETIRED MODERATOR Lifetime Supporter

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    Looking forward to pics and a range report...
     
  19. phideaux

    phideaux Well-Known Member Lifetime Supporter

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    Will do,

    May take a litte while, as weather is still a little nasty.


    Jim
     
  20. phideaux

    phideaux Well-Known Member Lifetime Supporter

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    Sorry it took so long, for me to get around to shooting this one.

    I took it out Friday evening, and shot it for the first time.

    Suppsedly it was boresighted from factory with the Nikon Prostaff scope. Which, btw, is a perfect match for this rifle.

    So ,to check where its POI and POA really are, I shot first shot at 25 yds, POI was 6 " low and 2 " left.
    Adjusted scope , 2 shots hit within an inch of center.
    Moved to 50 yds, 2 shots 1 " high and 1 " right.
    Moved to 100yds, 2 shots 1 1/2" right and 2 "high,

    8 clicks down and 6 clicks left on scope should get a dead center.

    Guess what, POI was in the bullseye, so I shot 6 rounds ,with all , but 1 touching bullseye ,which is 3/4" dia. All shots off bench ,using padded tripod.
    I really like Savage rifles a lot.


    [​IMG]

    Jim